asan.h

/* AddressSanitizer, a fast memory error detector.
   Copyright (C) 2011-2014 Free Software Foundation, Inc.
   Contributed by Kostya Serebryany <kcc@google.com>

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#ifndef TREE_ASAN
#define TREE_ASAN

extern void asan_function_start (void);
extern void asan_finish_file (void);
extern rtx asan_emit_stack_protection (rtx, rtx, unsigned int, HOST_WIDE_INT *,
				       tree *, int);
extern bool asan_protect_global (tree);
extern void initialize_sanitizer_builtins (void);
extern tree asan_dynamic_init_call (bool);

extern gimple_stmt_iterator create_cond_insert_point
     (gimple_stmt_iterator *, bool, bool, bool, basic_block *, basic_block *);

/* Alias set for accessing the shadow memory.  */
extern alias_set_type asan_shadow_set;

/* Shadow memory is found at
   (address >> ASAN_SHADOW_SHIFT) + targetm.asan_shadow_offset ().  */
#define ASAN_SHADOW_SHIFT	3

/* Red zone size, stack and global variables are padded by ASAN_RED_ZONE_SIZE
   up to 2 * ASAN_RED_ZONE_SIZE - 1 bytes.  */
#define ASAN_RED_ZONE_SIZE	32

/* Shadow memory values for stack protection.  Left is below protected vars,
   the first pointer in stack corresponding to that offset contains
   ASAN_STACK_FRAME_MAGIC word, the second pointer to a string describing
   the frame.  Middle is for padding in between variables, right is
   above the last protected variable and partial immediately after variables
   up to ASAN_RED_ZONE_SIZE alignment.  */
#define ASAN_STACK_MAGIC_LEFT		0xf1
#define ASAN_STACK_MAGIC_MIDDLE		0xf2
#define ASAN_STACK_MAGIC_RIGHT		0xf3
#define ASAN_STACK_MAGIC_PARTIAL	0xf4
#define ASAN_STACK_MAGIC_USE_AFTER_RET	0xf5

#define ASAN_STACK_FRAME_MAGIC		0x41b58ab3
#define ASAN_STACK_RETIRED_MAGIC	0x45e0360e

/* Return true if DECL should be guarded on the stack.  */

static inline bool
asan_protect_stack_decl (tree decl)
{
  return DECL_P (decl) && !DECL_ARTIFICIAL (decl);
}

/* Return the size of padding needed to insert after a protected
   decl of SIZE.  */

static inline unsigned int
asan_red_zone_size (unsigned int size)
{
  unsigned int c = size & (ASAN_RED_ZONE_SIZE - 1);
  return c ? 2 * ASAN_RED_ZONE_SIZE - c : ASAN_RED_ZONE_SIZE;
}

#endif /* TREE_ASAN */